John: We had problems with a new Dell laptop - 8th generation Intel Core i7 processor and good graphics - but with DaVinci Resolve 14 rather than Premiere Pro. The BlackMagic Design tech people in the UK were excellent and tried their best to find a solution or workaround for weeks, but couldn't identify exactly why it was going wrong. An update for Windows 10 was identified as being at least partly responsible for the sudden failure. We then experienced exactly the same failure for Sony Catalyst Browse and Prepare, probably not a coincidence. Since, we've been fine with Magix's Vegas Pro 15 Edit.
So, at least generally, you're not alone. Today's technology is great when it works but frustrating when it doesn't, as we assume the former as norm (usually with good reason).
I hope you soon find a solution. BlackMagic Design's DaVinci Resolve 14 (free version) is excellent, even if we're sadly unable to use it on our Dell laptop, and it's winning over previous users of Premiere Pro for good reason.